All JavaScript apps run in the browser with its own JS engine (V8 in chrome) garbage collection, etc. This is effectively a VM I think. Like you deploy Java app

All JavaScript apps run in the browser with its own JS engine (V8 in chrome) garbage collection, etc. This is effectively a VM I think. Like you deploy Java apps to the JVM, you deploy JavaScript apps for the “browser VM.” Google writes gmail but they also write chrome and V8, so they are in a unique position of writing both the application and the platform it runs upon. Presumably this would allow them to make something more performant than most, not less.